Muffler



Jan. 17, 1 928.

E. P. GRAY MUFFLER Filed Feb. 17 1923 2 Sheets-Sheet l m w W q P 4. W W 2 Z Y M $11 m i 1 .239330 0 o r 0666' P; \Y ooooooosem L (ittmg Jan. 17, 1928. 1,656,629

E. P- GRAY MUFFLER Filed Feb.l7 1923 2 Sheets-Sheet mlentam 59 a? P Q22 (filo meg 5 get'out of order and rattle.-

pressure so that the Another object of the invention is to several novel features of Patented Jan. .17, 1928.

UNITED STATES PATENT oFFJcE.

Emu: r. eaav, or nar'no rr, MICHIGAN. HDTFLEB. Application filed February i7, 192:. s rial no. 619,744.

. This invention relates to mufii ers and the I object of the invention is to provlde a mufller' for internal combustion engines in which the back pressure is reduced to a mmlmum.

5 Another object of the inventionis to provide a muflier of very simple construction and of consequent low manufacturin cost] and having an efiiciency above that o mufflers of the usual type. A further ob ect of the invention is to provide a muflier of the character described which is adapted to replace the normal exhaust pipe extendin beneath the body of the automobile an which when secured in place has no parts to Another objectof the invention is to provide .a mufller in whichthe flow oiigases' therethrou h is in one general direction due to the deslgn and length of the mufiier so that the exhaust gas is not turned back upon itself as is the case with the short cylindrical types of mufflers. A further object of the invention is to provide a 'muflier in which the exhaust gases enter the intake end thereof .in distmctimpulses from the internal combustion engine and are discharged at a steady uniform explosions is completel. done away with. pro-- vide a mufiier to which a heater may be attached intermediate its ends at. a pomt where the gases are partially expanded so that the impulse of the se arate explosions is considerably reduced be ore the gases are carried to the heater. These objects and the the inventionlare hereinafter more fully described and claimed and the preferred form of construc-' tion by which these objects are attained is shown in the accompanying drawings which? Fig. 1 is a view of the muffler. as used with an automobile of the usual type. Fig. 2 is a side'view of a muflier embodyin my invention. f F%ig. 3 is a section taken on'line 2+2 of Fig. 4 is a segtion taken on line of F1 3. Y Y r Fig. '6 is a section taken on hne ,H of

with recessed portions 2, 3

noise of the separate 1 3. V several flanges t fig. 5 is a section'taken on line 5 -5 0f ases.

. Fig. 7 is a perspective viewof the central portion of the mufiier.

Fig. 8 is a perspective view showing how.

the parts are secured together.

' Fig. 9 is a section showing am alternative manner of, securing the parts together.

Fig. 10 is. a view showing the construction at the valve secured to the center of the muf- Fig. 11 is-a view with the upper half of the outer casing removed showlng an alternative type of interior arrangement of the mufiler. a

As shown in I adapted to'be connected at the forward'end to the exhaust manifold of the internal combustionengine and when used on automobiles the muflier takes the place of the usual long exhaust pipe and extends beneath the automobile body. The muflier comprises two duplicate inner parts one of which is shown in. Fig. 4. Each .part 1 is provided halffround in cross section shown in Fi 5, 6. and 8. The portion 2 is of greater diameter than the portion 3 and the portion 3' 1s of greaterdiameter than the portion the said, portions tapering in diameter. from the forward end to the rearend of the memher 1. The two parts 1 are positioned with the flat flanges engaging as shown in Fi 5 and as the two parts 1 are exact duphcates the portions 2, 3 and 4 when placed together form cylindrical recesses. The time 2, 3 and 4 areprovided with a multiplicity of small apertures 5... The 'outer cas ing is also. cpmposed of two duplicate parts one of which" is shown in Fig. 2. Each lindrical portions 6 and 7 of greater diam,-

' 'et'er than the portions 2, 3 and 4 of the memhers I and are adapted to fit thereabout as ea peripheral flange 8 is shown in-Fig. 5. A provided about each portion of the outer I casing and one flange on each portion of the outer casing is adapted to be bent over the portions 1 and flange 8 of the opposite casin as shown in Fig. 5. The us secured together are then welded togetherso as to form a leak proof jointzto prevent the escape of exhaust The portions 6 and 7 are reduced in iaineter at the center as shown in Figs. 8

Figs. 1 and 2 the 'mufller is and 4 which .a're

por-

half of the outei casing compi'ises two semi-cy-- As shown in Fig. 10 a valve portion 12 is provided having an aperture registering with the apertures 10 and 11 of the mufiler and this valve portion is secured to the mutfler by the screws 13 which the flanges of the mufiier and into threaded apertures provided therefor in the valve portion 12. A rotatable shaft 14 is provided to which the valve l'5'is secured and an arm 16 is provided which may be moved to the dotted position shown in Fig. 10 to close the valve. When the valve is in the open position shown in dotted lines in Fig. 10 it extends down through the apertures 10 and 11 and restricts the passageway thus causing the gases to pass upwardly through the valve and through a heater which may be connected thereto as will be readily understood,'the direction'of flow at the gases being indicated by the arrow at the right of- Fig. 10. When the valve is closed by moving the lever 16 to the dotted position the passageway for the exhaust gases is not restricted and the, entire quantity of exhaust gases may pass directly through the chamthe apertures 5 in interna in the cylinders of the engme ber 3 of. the muflier.

The flow of exhaust gases 15.. shown more i particularly in Fig. 3 in which the gases enter in the direction of the arrows at the left of Fig. 3 and pass outwardly through the apertures 5 in the chamber 2 and thence into the chamber 17 between the inner and outer casings. The gases then pass through the chamber 3 and through the chamber 3 and outwardly through the apertures 18 in the opposite end thereof into the chamber l9between the inner and outer casings and thence through the apertures 5' into the chamber 4 andthence to atmosphere. Ipreferablyprovide a tail piece 20 for the muflier composed of two partswhich when secured together are secured to the muflier by" bolts 21 and form a conduit 22 through which the exhaust gases may pass, the diameter of the conduit 22 decreasing toward the discharge end. Due to the operation of the combustion engine the exhaust gases are discharged into the mufller in separate impulses caused by the explosion of gas but by ecreasing the diameter of the chambers 2, 3 and 4 and conduit 22 the flow of exhaust sis retarded so thatit passes from the ischarge end 23 uniformlywithout impulse or sound. In order to produce this result the 4 muflier must be carefully desi ned so that .the

cient to put a restriction to flow. is not 5 extend through merged to produce a continuous flow of ex-' haust gases from the discharge end without building up pressure in the mufiier.

A slightly alternative 'form is shown in .Fig. 11 in which one half of the outer casing has been removed. The exhaust gases enter the chamber 24 of the inner casing and the flanges of the inner casing divide the outer casing into two compartments or chambers extending lengthwise of the muflier. The gases pass from the exhaust manifold into the chamber 24 and through the apertures 25 into the chamber on the upper side of the flanges 26 and pass through t (of the muflier and through the ap'ertures'27 in the flanges 26 into the chamber between ab e' length the casings on the lower side of the flanges. Y

on the lower side which are shown in dotted lines and are open to the chamber between the inner and outer casings on the lower side of the flanges 26. These apertures 30 are provided to relieve pressure when a backfire occurs in the muffler and the exhaust gases pass from the apertures 30 through the lower chamberbetween the casngsand into the apertures 29 and through the chamber 28 to atmosphere. If the apertures 25 were the only means of exit from the chamber 24 a backfire would-produce pressure on one side only ,of the inner casing and would warp the mufller out of shape, but by providing the apertures 30 the pressures are equalized on each side of the chamber 24 so'that the inner casing will not be forced out of shape. This t pe of mufiler while not varying greatly rem the type shown in Fig. 3 causes the gas to travel a greater distance before being discharged.

From the foregoing description it becomes evident that the device efiicient in operation, is composed of few arts and is of consequent low manufaucturmg cost, may be easily assembled and pro- .vides a device which accomplishes the obbetween the casings into two parts, the in ner casing being adaptedto receive exhaust is very simple and.

gases .and being formed of a series of chambers closed one to the other, the chambers of the inner casing having apertures wherebythe gas passes from the inner casing to the chamber between the casings and thence to the next chamber of the inner casing, there being an aperture provided inboth casings at the intermediate point of contact permitfi gases from the mufller subse-' ting flow of quent to a partial expansion of the gases, and a valve for controlling the said aperture adapted when moved to open the aperture to extend into the passageway for gases.

' 2. A mufller comprising an outer tially cylindrical sheet metal member formed of two flanged parts, an inner sheet metal h casing'formed of two similar flanged parts, the flanges of both casings being secured together and fixedly supporting the inner casing within the outer casing providing a chamber between thecasings closed to atmosphere and theinner casing being formed of separate chambers provided with aperspaced relation parts each of gases from one tween the flanges of the outer casing, theseveral flanges eing secured together to seal the same and positioning the inner casing in providing chambers'exteriorly of the inner casing and on opposite sides of the flanges thereof, there. the inner casing and flanges whereby gases passing into the inner 'casing pass into the said chambers on opposite sides of the'inner casing and thence to a succeeding chamber of the inner casing.

4. A mufiler comprising an. outer casing of sheet-metal formed of two similar half parts, an inner sheet metal casing enclosed thereby also formed of two similar half provided with flanges of the inner casing being utilized to support the same centrally within the outer casing and the'in'ner casing beingarranged to receive the exhaustgases at one'en'd, and a tail pipe at the opposite end of the inner casing.

formed or two parts, each partbeing formed to provide a-series of longitudinal pockets casing :formed of two parts 'forming cham- .bers about the inner casing when secured to substanthe inner casing formed of two similar half with the outer, casing and.

mgapertures provided in flanges and extending longitudinally of the outercasing, the i1 arrangement providing for ends to provide an obstruction 5. A mufiier comprising an inner casing apertured, and an outer and the two parts when secured together fl completely enclosing the pockets, an outer l ward of the obstruction and apertured to allow pocket to the outer ceeding pocket. 7

6. A muflier comprising an outer casing of sheet metal formed of two similar flanged parts together forming a hollow casing, an inner silencing member also of two similar anged parts together providing a series of .hollow chambers in alignment longitudinally and separate one from the other, the inner member being in spaced relation with the outer casing providing a chamber therebetween the flanges of the inner member being supported between the flanges of the outer member and the walls of the inner chambers aving apertures, the wall of the outer member being reduced intermediate its length to closely engage the wall of an inner cham-- her, the arrangement providing for a flow of fluid from an inner chamber to a surround ing chamber and thence toan inner chamber successively from end to end of the device.

A mufier formed of sheet metal comprising an outer cylindrical shell of two similar half parts flanged at each edge and an inner silencing member of sheet metal parts flanged at each edge, each inner half part having depressions formed therein providing separate chambers when the two inner partsare placed together, the flanges of-the two inner parts being secured between the flanges of the two outer parts forming two chambers of the space between the inner and outer shells, the walls of the said pockets having apertures providing for communication between the inner and other chambers.

8. A metal mufller comprising an outer sheet metal shell formed of two parts each provided with a lateralflange at each edge,

an inner silencing member'in spaced relation with the outer shell providing a chamber therebetween, the inner member being formed of two similar parts provided with a lateral flange at each edge and formed to provide a series of longitudinal pockets apertured to provide communication between the inner silencing member and the chamber between theinner and outer members, the flanges of the inner member being secured between the anges of theassembled outer member, the an intake of gases at one end and a discharge thereof at the other.

9. In a mufiier,

an exhaust conduit, the walls of which are flattened intermediate the preventmg the passage of the gases therethrough, the

said walls each side of the obstructionbeing casing of sheet metal the tubular member into which the exhaust gases are discharged from the conduit forfrom which the communication from one chamber to the next sucattened at its ends to clamp about the tubu .ar member and providing a chamber about gases pass to the exhaust. conduit to the rear of the obstructiom 10. In a muflier, a tubular member providing a passageway for exhaust gases, said member having an obstruction intermediate its ends preventing the passage of the gases longitudlnally therethrough, said tubular member having apertures forward of and to the rear of the obstruction for the escape and the reentrance respectively of the exhaust gases and an outer sheet metal shell flattened at its ends to clamp about the tubular member and positioned to receive the exhaustgases discharged from the forward series of apertures and to guide the same to the rear series of apertures.

11. A mufller comprising an outer caslng of sheet metal formed of two similar half parts, the end portions thereof being contracted to form apertures of smaller diameter than the diameter of the casing, an inner sheet metal casing also formed of two simil 3L1" ded with complemental half parts provi flanges extending longitudinally of the outer casing, the contracted end portions of the outer casing engaging about and clamping the inner casing at the ends, the flanges of the inner casing being utilized to support the same centrally within the outer casing and the inner casing being arranged to receive the exhaust gases at one end and atail pipe through which the gases are discharged beyond the mufiler at the opposite end.

In testimony whereof, I sign this specification.

EMMET P. GRAY. 

